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PatchSiren cyber security CVE debrief

CVE-2026-33760 langflow-ai CVE debrief

CVE-2026-33760 is an IDOR/BOLA vulnerability in Langflow's /api/v1/monitor router. The vulnerability allows any authenticated user to read, modify, rename, or permanently delete another user's data by supplying the target's resource ID or flow_id. This issue was fixed in Langflow version 1.9.0. The vulnerability has a CVSS score of 8.8 and is classified as HIGH severity.

Vendor
langflow-ai
Product
langflow
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-23
Original CVE updated
2026-06-26
Advisory published
2026-06-23
Advisory updated
2026-06-26

Who should care

Langflow users, administrators, and security teams should be aware of this vulnerability and take immediate action to update to version 1.9.0 or apply necessary mitigations. Authenticated users with access to the /api/v1/monitor router are potentially impacted.

Technical summary

The /api/v1/monitor router in Langflow exposes 7 endpoints that perform read, write, and delete operations on user-owned resources without verifying ownership. This allows unauthorized access to messages, sessions, build artifacts, and LLM transaction logs. The vulnerability is caused by inconsistent application of ownership checks, as demonstrated by a correctly implemented endpoint in the same source file.

Defensive priority

High priority should be given to updating Langflow to version 1.9.0. In the meantime, restrict access to the /api/v1/monitor router and implement additional monitoring to detect potential exploitation attempts.

Recommended defensive actions

  • Update Langflow to version 1.9.0 or later
  • Restrict access to the /api/v1/monitor router
  • Implement additional monitoring to detect potential exploitation attempts
  • Review and update access controls for user-owned resources
  • Consider applying compensating controls to mitigate the vulnerability

Evidence notes

The CVE record and NVD detail provide official information about the vulnerability. The source item URL provides additional context from the NVD database. The mitigation or vendor reference provides guidance on fixing the issue.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-33760 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-33760

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-33760 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-33760

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.